Efficacy of tendon stem cells in fibroblast-derived matrix for tendon tissue engineering

Background aims. After injury, tendons often heal with poor tissue quality and inferior mechanical properties. Tissue engineering using tendon stem cells (TSCs) is a promising approach in the repair of injured tendon. Tenogenic differentiation of TSCs needs an appropriate environment. More recently, the acellular extracellular matrix (ECM) generated from fibroblasts has been used to construct various engineering tissues. In this study, we successfully developed an engineered tendon tissue formed by seeding TSCs in de-cellularized fibroblast-derived matrix (dFM). Methods. Patellar TSCs and dermal fibroblast were isolated and cultured. Using the method of osmotic shock, dFIVI was obtained from dermal fibroblast. ECM proteins in dEM were examined. TSCs at passage 3 were seeded in dFM for 1 week. Proliferative capacity and characterization of TSCs cultured in dFM were determined by population doubling time, immunofluorescence staining and quantitative reverse transcriptase polymerase chain reaction. Engineered tendon tissue was prepared with dFM and TSCs. Its potentials for neotendon formation and promoting tendon healing were investigated. Results. dFM is suitable for growth and tenogenic differentiation of TSCs in vitro. Neo-tendon tissue was formed with tendon-specific protein expression when TSCs were implanted together with dFM. In a patellar tendon injury model, implantation of engineered tendon tissue significantly improved the histologic and mechanical properties of injured tendon. Conclusions. The findings obtained from our study provide a basis for potential use of engineered tendon tissue containing dFM and TSCs in tendon repair and regeneration.